Guide member and method for integral foam molding

ABSTRACT

According to the invention, a novel guide member for integrally forming the fastening parts with the urethane mold and an integral molding method using the guide member are provided. The guide member includes a guide body that has an extended body which includes concave cross-section and at least one open end (4, 7), and isolation members (5, 6) provided near the ends of said guide portion. The isolation members are detachable, and by engaging with the fastening surface of the fastening parts, they effectively block any seepage of liquid foaming raw material. With the integral forming method using said guide member of the invention, it is possible to embed the ends of the fastening parts within the urethane molding and to improve its peeling strength at low cost.

TECHNICAL FIELD

The invention concerns a member for integrally forming a foam materialsuch as urethane; specifically, it concerns a guide member foradhesively fixing a fastening part to a urethane molding.

BACKGROUND ART

Cushion material in which the covering material is put onto urethane isgenerally used in seats in automobiles and other vehicles and aircraft,in chairs for home or office use, or in door linings or interiorappointments. The urethane and covering material are usually puttogether detachably using a fastening part that is fixed to a urethanemolding.

In order to provide fastening parts on the urethane surfaceinexpensively and stably, the integral forming of urethane and fasteningparts has been implemented. In the prior art, the fastening parts arepreviously covered so that the liquid foaming raw materials do notadhere to the surface of the fastening parts, then the liquid foamingraw material is flowed in, and thereafter portions to which the materialis attached are cut away.

With the conventional method, in order to prevent the liquid foaming rawmaterial from adhering to the fastening surface, it has been necessaryto pre-manufacture guide members which are the same length as eachfastening part and fit into a urethane metal mold. That is, the guidemember must be remade for each desired length of fastening part, whichcauses an increase in the fabrication time and cost. In addition,additional equipment is needed for each fastening part to prevent theliquid foaming raw material from flowing onto the fastening surface,which results in increasing of the cost and the number of operatingprocesses. Another drawback of the conventional method is that becausethe fastening part has a relatively low peeling strength, the coveringmaterial of the cushion material easily peels off.

Thus the purpose of the invention is to provide a novel guide memberthat reduces cost and the number of processes.

Another purpose of the invention is to provide a novel guide member thateffectively cuts off the seepage of liquid foaming raw material onto thefastening surface.

A further purpose of the invention is to provide an integral moldingmethod that improves the peeling strength of the fastening part.

DISCLOSURE OF THE INVENTION

In order to achieve the above purposes, the invention comprises thefollowing means.

According to the invention, the guide member for forming the fasteningpart integrally with the urethane molding has a longitudinally extendedbody that has a concave cross-section and at least one open end. Thesurface of its inner walls contact with side surfaces of said fasteningpart to prevent the flow of liquid foaming raw material to the fasteningsurface.

In addition, to prevent said liquid foaming raw material from seepinginto the fastening surface of the interior of said guide member, saidguide member may also include at least one isolation member near atleast one of its ends. The isolation member is provided such that itengages with the fastening surface of said fastening part.

Moreover, the height of the inner wall of the guide member of theinvention may be formed so that it is higher than the height of thefastening parts.

The isolation member is preferably a detachable thin plate made ofspring material, and said guide member is preferably made of aluminum oraluminum alloy.

The method of the invention for integrally forming a fastening part withthe urethane mold, comprises the steps of:

setting the isolation member to the desired position on the fasteningpart;

attaching said fastening part to said guide member so that it extendsoutwardly from at least one end of said guide member;

fixing said guide member to the urethane metal mold;

flowing liquid foaming raw material into said urethane metal mold; and

removing said guide member and said isolation member after apredetermined time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a preferred embodiment of the guide member of the inventionshown in perspective and show in an elevational cross-sectional view inthe longitudinal direction in FIG. 1B taken substantially along the line1B--1B of FIG. 1A.

FIG. 2A shows the fastening part of the invention;

FIG. 2B is a fragmentary perspective view of the fastening partpositioned in relation to the guide member of FIG. 1A;

FIG. 2C is a fragmentary sectional view taken substantially along theline 2C--2C of FIG. 2B.

FIG. 3 is an elevational cross-sectional view of cushion materialproduced by the integral molding method of the invention.

FIG. 4A is another embodiment of the guide member of the inventionhaving the isolation members of FIG. 1 with an end sealed off;

FIG. 4B is a longitudinal sectional view taken substantially along theline 4B--4B of FIG. 4A;

FIG. 4C is another embodiment of guide member with double isolationmembers;

FIG. 4D is a longitudinal sectional view taken substantially along theline 4D--4D of FIG. 4C;

FIG. 4E is another embodiment of guide member with weirs at both ends;

FIG. 4F is a longitudinal sectional view taken substantially along theline 4F--4F of FIG. 4D;

FIG. 4G is another embodiment of the guide member having the isolationmembers of FIG. 1 and the weir members of FIG. 4E; and

FIG. 4H is a longitudinal sectional view taken substantially along theline 4H--4H of FIG. 4G.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the invention are described in detail,making reference to the drawings.

FIG. 1 is a preferred embodiment of the guide member 1 of the invention.Guide member 1 for integral molding of the fastening parts with theurethane molding comprises guide portion 2, which has an longitudinallyextended body having a concave cross-sectional opening at ends 4 and 7,and isolation members 5 and 6 positioned somewhat inwardly from saidends 4 and 7 so as to be perpendicular to longitudinal axis.

Said guide portion 2 is preferably made of aluminum or aluminum alloyand is manufactured by extrusion molding or injection molding. Thelongitudinal length of the guide portion varies depending on that of thefastening part and the structure of the cushion material, but the heightof inner wall 3 is preferably 6-8 mm.

The width of the inner side of the guide member is substantially equalto the width of the fastening part, so that when the fastening part isattached, the side surface of the fastening part and the inner sidesurface 3 of the guide member are contacted tightly. Also, a bottomsurface 10 of guide member 1 is completely flat so as to be fixed firmlyto the urethane metal mold.

The isolation members 5 and 6 are preferably thin plates made of springmaterial, alternatively they may be in the shape of the letter C. Theymay also be made from any other materials that do not easily deform anddegrade. The isolation members 5 and 6 are preferably located detachablyto the inner wall surface of the guide member, and they may be fixed ata predetermined position. The plate thickness of said isolation members5 and 6 is preferably 0.2 mm. Their height is preferably 1.5 mm,corresponding to the height of the stem of the fastening part.

FIG. 2 shows how the fastening part is attached to the guide member ofthe invention. FIG. 2(A) shows a conventional fastening part 20comprising stems 21, base 23, and anchor portions 22 which extendparallel in the longitudinal direction.

FIG. 2(B) is a perspective view showing how fastening part 20 isattached to guide member 1 of the invention. The fastening part is noteasily dislocated, because inner side surface 3 of the guide member 1firmly contacts the side surface of base 23 of fastening part 20 or theside surface of anchors 22. The inner side surface 3 of the guide member1 functions to prevent the flow of liquid foaming raw material to stems21 when said liquid foaming raw material flows from above in thedrawing. In the drawing, end 24 of the fastening part substantiallycoincides with end 4 of the guide member 1, but it is preferable to setit somewhat inwardly in consideration of the expansion of the fasteningpart due to the heat of reaction. The height of inner wall 3 of theguide member 1 is preferably the same as that of fastening part 20.Alternatively, the height of inner wall 3 may be higher than that offastening part 20. In that case, a narrow groove (not shown) is formedin both sides of the fastening parts on the urethane when it isintegrally formed. These narrow grooves allow the fastening part,although anchored in the urethane, to flexibly accommodate the movementsof the user.

FIG. 2(C) is a longitudinal cross-sectional view of FIG. 2(B). Theisolation member 5 of the guide member of the invention is providedsomewhat inwardly from a guide end 4. The thickness of the isolationmember is preferably 0.2-0.4 mm, which is about half of the distancefrom one stem to the next stem (0.5-0.7 mm), and its height issubstantially equal to that of stems 21 (1.5 mm). Because of thisstructural feature, the isolation member of the invention can be engagedbetween the rows of the stems as shown in the drawing. The isolationmember preferably can move freely and is detachable so that it can beput in any desired position on stem surface 21 of fastening part 20. Theisolation member 5 functions to effectively prevent foaming raw materialfrom penetrating through guide end 4 and to completely isolate theinterior region of the isolation member from its exterior. The drawingshows only one side of the guide member, but it should be noted that theend on the other side is similar.

FIG. 3 is a longitudinal cross-sectional view of cushion materialmanufactured by an integral molding method using the guide member of theinvention. According to the method of the invention, as the first step,said isolation members 5 and 6 are engaged in predetermined position onstem 21 of said fastening part 20. As the second step, it is attached tothe interior of said guide member so that ends 32 and 33 of saidfastening part 20 respectively protrude from ends 4 and 7 of said guidemember 1 of the invention. As the third step, bottom surface 10 of guidemember 1 is fixed firmly to the urethane metal mold (not shown).Finally, liquid foaming raw material is flowed into said urethane metalmold and is allowed to foam, and thereby urethane molding 31 andfastening part 20 are formed integrally. Thereafter, guide member 1 andisolation members 5 and 6 are removed.

When the foaming raw material is flowed on the bottom surface of thefastening part 20 within the guide member 1 and it foams, the anchorportions 22 are inserted into the foam, anchoring the fastening part 20to the foam. Protruding portions 32 and 33 of fastening part 20 becomeembedded into the urethane mold by length a. The length of embeddedportion can be adjusted, and either one side or both sides of saidfastening parts can be embedded. According to the invention, the endportions 32, 33 of the fastening part 20 of the cushion material areembedded into the urethane molding, thereby it does not easily peel off.Therefore, it is an advantage that the fastening part 20 of theinvention has higher peeling strength than prior art.

With the guide member 1 of the invention, the peeling strength can bealso improved without embedding the fastening part 20 into the urethanemolding. If isolation members 5 and 6 are respectively located inwardlyfrom each ends of guide member 1 of the invention, liquid foaming rawmaterial can be completely cut off by the isolation members 5 and 6after a little penetration. As a result, only the surface near both endsof the fastening part 20 is covered with foam, making it harder to peeloff. The peeling strength in this case can be adjusted by a location ofthe isolation members 5, 6.

By the aforementioned method, not only the need for additional parts butalso the need for operations such as strict scaling of the length of theguide member 1 to the length of a fastening part 20 are eliminated,thereby production costs can be greatly reduced.

FIG. 4 shows another embodiment of the guide member of the invention.FIG. 4(A) is a guide member whose only one side is opened and the otherside end is sealed off with a wall with respect to the guide member 1 ofthe preferred embodiment of the invention shown in FIG. 1. FIG. 4(C)shows another embodiment which includes double isolation members of thepreferred embodiment of the invention. FIG. 4(E) shows anotherembodiment which includes a weir board made of the same material as saidisolation member and provided on both end surfaces of the guide portion,instead of the isolation member of the preferred embodiment. FIG. 4(G)shows another embodiment which includes the isolation members of thepreferred embodiment and the weir boards of FIG. 4(E), wherein thepreferred embodiment is combined with the embodiment of FIG. 4E.

It will be clear to one skilled in the art that other various guidemember structures are possible by combinations or variations of theabove embodiments.

The guide member of the invention eliminates the need for any additionalequipment or additional processes and makes it possible to effectivelyprevent the seepage of liquid foaming raw material onto the fasteningsurface.

According to the integral molding method of the invention using saidguide member 1 of the invention, the need for any additional equipmentor the need for a strict scaling process are completely eliminated,thereby it is possible to easily provide fastening parts with highpeeling strength.

As a result, production costs of cushion material are greatly reduced,and throughput is greatly improved.

I claim:
 1. A guide member for integrally forming a urethane foammolding with a fastening part having a base with projecting stemsforming a fastening surface and having anchors comprising, a guideportion having a longitudinally extending body that has a concavecross-section forming a bottom surface joining a pair of spaced innerwall surfaces and at least one open end, and the guide memberaccommodates the fastening part so that the side surfaces of the base ofthe fastening part contact said inner wall surfaces of said guideportion to prevent the flow of foam to the fastening surface and so thatthe stems of the fastening part contact said bottom surface of saidguide portion.
 2. A guide member as described in claim 1 wherein saidguide member is made of aluminum or aluminum alloy.
 3. A guide memberfor integrally forming a fastening part with a urethane moldingcomprising, a guide portion having a longitudinally extending body thathas a concave cross-section forming a bottom surface joining a pair ofspaced inner wall surfaces and at least one open end, and the guidemember accommodates said fastening part so that the side surface of saidfastening part contacts said inner wall surfaces of said guide member,said guide member further including at least one isolation memberprovided near at least one end of said guide member and contacting saidbottom surface, said inner wall surfaces and said fastening part so asto prevent the seepage of said liquid foaming raw material into saidguide member.
 4. A guide member as described in claim 3 wherein saidisolation member is a thin plate made of spring material.
 5. A guidemember as described in claim 4 wherein said guide member is made ofaluminum or aluminum alloy.
 6. A guide member as described in claim 3wherein said guide member is made of aluminum or aluminum alloy.
 7. Aguide member for foaming urethane into a molded article with an integralfastening part having a base with projecting stems and anchorscomprising, a guide portion having a longitudinally extending body thathas at least one open end and a concave cross-section forming a pair ofspaced inner wall surfaces that engage the base of a fastening partpositioned therein to prevent passage of urethane therebetween to thestems during foaming, and an isolation member positioned proximate eachsaid open end and contacting said inner wall surfaces to prevent passageof the foaming urethane to the stems in said guide portion.
 8. A guidemember as described in claim 7 wherein the height of said inner wallsurfaces is higher than the height of a fastening part.
 9. A guidemember as described in claim 8 wherein said guide member is made ofaluminum or aluminum alloy.
 10. A guide member as described in claim 8wherein said isolation member is a thin plate made of spring material.11. A guide member as described in claim 10 wherein said guide member ismade of aluminum or aluminum alloy.
 12. A guide member according toclaim 7, wherein said isolation member is removable for selectivepositioning longitudinally of said guide portion.
 13. A guide memberaccording to claim 7, wherein said inner wall surfaces are joined by abottom surface, said isolation member being sized to contact said innerwall surfaces, said bottom surface and the base of the fastening part.14. A guide member according to claim 13, wherein said isolation memberis sized to fit between the stems on the fastening part at differentpositions.
 15. A method for integrally forming a fastening part with aurethane molding, comprising the steps of:setting an isolation member toa desired position between stems of the fastening part; attaching saidisolation member within spaced inner wall surfaces of a guide memberwith the fastening part extending outwardly from at least one end ofsaid guide member; fixing said guide member to a urethane metal mold;flowing liquid foaming raw material into said urethane metal mold; andremoving said guide member and said isolation member after apredetermined time.
 16. A method for foaming urethane in a mold into amolded article with an integral fastening part comprising the stepsof:constructing a fastening part having a base with oppositelyprojecting stems and anchors, setting one or more isolation members atpredetermined positions between stems of said fastening part, locatingsaid isolation members and said fastening part interiorly of a guidemember forming a bottom surface joining a pair of spaced inner wallsurfaces, with said base of said fastening part, said bottom surface andsaid inner wall surfaces of said guide member and said isolation membersenclosing said stems of said fastening part, fixing said guide member tothe mold, flowing foaming urethane into the closed mold, and removingsaid guide member and said isolation members after completion of thefoaming of the urethane.
 17. A method according to claim 16, furthercomprising the steps of:constructing said fastening part of a greaterlength than the length of said guide member, locating said fasteningpart relative to the guide member so that at least one end of saidfastening part protrudes from one end of said guide member, whereby saidone end of said fastening part is embedded in foamed urethane to provideimproved peeling strength.
 18. A method according to claim 16, furthercomprising the steps of:selecting the positions of at least one of saidisolation members a predetermined distance inwardly of one end of saidguide member, whereby said one end of said fastening part is embedded infoamed urethane to provide improved peeling strength.